We aimed to evaluate the prevalence and risk factors of professional drivers' vigilance disorders in Morocco. This transversal epidemiological multicentric study concerned 5,566 professional drivers of taxis (2,134), buses (1,158) and trucks (2,274). We used an anonymous individual questionnaire of 4 sections: socioprofessional and sanitary characteristics of drivers, working conditions, sleeping habits, symptoms of sleep problems and favouring factors. Drivers were a population at risk: high body mass index (62.2%), toxic habits (smoking: 50.6%; alcohol: 12.9%; cannabis use: 11.7%), pathological antecedents (27%) and consumption of psychotropic drugs (4%). Their working conditions were difficult and sleeping problems were frequent. The mean daily hours of work was 10.6 ± 1.6, and mean sleep duration 6.5 ± 1.3 hr. Insomnia was 40.2%, abnormally high Epworth scores 36.3% and sleepiness when driving 53.4%. Information and education on the dangers of sleepiness while driving is necessary, as is respect for regulations on work duration. The extension of the occupational health system to this type of activity would help improve road security and protect the health of professional drivers and road users.